Improvement in sewing-machines



3 Sheets-Sheet 1. W. P. UHLINGER. 2

Sewing Machine.

No. 21,224. Patented Aug. 17, 1858.

2 7762?}: eases.- I n wnior 3 Sheets-Sheet 2.

Patented Aug. 17, 1858.-

W. P. UHUNGER.- Sewing Machine.

UNITED: STATES PATENT OFFICE.

W. P. -UHLINGER, OF PHILADELPHIA, PENNSYLVANIA.

|MPROVEMENT IN SEWING-MACHINES.

To aZZ whom it may concernw Be it known that I, WVILLIAM P. UI-ILING-ER, of the city of Philadelphia and State of Pennsylvania, have inventeda new and useful Improvement in Sewing-Machines; and I do hereby declarethe following to be a full and exact description of the same, referencebeing had to the annexed drawings, making a part of this specificati on,in which- Figure 1 is a view of the bottom of my ma chine; Fig. 2, aperspective view of the same. Fig. 3 is a sectional view of the end ofthe machine. Figs. 4, 5, 6, and 7 are views of detached parts of themachine.

My improvement relates to machines which use the double-chain stitch,and has for its object the expansion of the loop of the under thread, soas to insure its being caught by the needle as it descends.

'A B CD represent the bottom or bed-plate of the machine inverted.

E, Fig. 8, represents the needle, which vibrates up and down by a shaftwith a cam or crank movement, F F, as shown in Fig. 3, in the mannercommonly practiced on sewingmachines.

G is the vibrating looper, which is attached to a small vibrating shaft,H H, which is worked by a cam, I I, and arm K, attached to the extremityof the shaft H. As the needle descends and forms the needle-100p incoming up the vibrating looper enters the needle-loop.

In order to secure the needle catching the under thread while comingdown, I have added the device L to the under side of the machine, whichis a vibrating finger, so attached and operated that its point catchesthe under thread just before the needle and carries it away from thelooper, seas to allow an increased space for the needle to enter andcatch the under thread. This finger L is attached at M as a pivot, andis vibrated back and forward to a sufficient extent and at the properintervals by a rod, N N, having a projecting arm, 0, at its extremity,which arm has a small friction-roller, which fits on two campieces, P P,on the side of the driving or main cam-wheel. As this wheel revolves thearm 0 and rod N N are vibrated backward and forward at the properintervals and to any desired extent, which maybe determined by the formgiven to the cam-pieces P and P.

Specification forming part of Letters Patent No. 21,224, dated August17, 1858; antedated May 3, 1858.

The operation of this new combination is as follows: The needle descendswith its thread, and as the needle ascends again a loop is formed. Thevibrating looper G then enters the needle-loop just formed and holds itwhile the vibrating finger L carries the under thread and spreads itaway from the looper, to allow the needle to descend again between theunder thread and vibrating looper, in order to catch the under thread,by which operation the loop-stitch is completed.

I have also improved the feed arrangement as follows:

R B, Fig. 3, and also Fig. 5, represents the feed-pad, which is a leverhaving its fulcrum at r r, the bottom of the conical cavity 1' r 0" 1".I The lower end of this lever is roughened. This lever is vibratedbackward and forward at the proper interval by the cam S S S S, whichworks on an arm, T T, attached to the side of the lever B R. A spring,'1), bears against this arm T T and keeps it against the cam. By thejoint action of the cam S S S S and spring 2) the lower extremity of thefeedpad is moved backward and forward.

The feed-pad is kept down by a spring, 1;, which presses against an arm,W, which is permanently attached to the feed-pad R R. The pressure ofthis spring is relieved whenever the feed-pad is moving backward bymeans of a projection, 00, on the cam-wheel F F, which elevates thelever w. The operation of this arrangement is as follows: The fabric isfed forward by the movement of the cam against the feed-lever, and atthat time the pressure of the spring is made to bear upon the lever B R,near the fulcrum r 1-. IVhen the feed is moved backward, the pressure isre moved from the feed-arm, as above described, by the proj ection xelevating the spring-leverw.

I do not desire to claim the vertical arm described in my specification,as that has been used before; but

That I do desire to claim, and secure-by Letters Patent, is-

The vibrating finger L,in combination with the needle and looper,arranged and operating substantially as above described.

WV. P. UHLINGER. Vitnesses:

J. H. B. JENKINS, SAML. R. G-URNMERE.

